Legumes are a staple of diets all around the world. In some least developed countries, they are the primary source of protein; however, their beneficial properties go beyond their nutritional value. Recent research has shown that legumes have bioactive compounds like peptides, polyphenols and saponins, which exhibit antioxidant, antihypertensive, anti-inflammatory and other biological activities. Thus, these compounds could be an alternative treatment for inflammatory diseases, in particular, chronic inflammation such as arthritis, obesity and cancer. Nowadays, there is a growing interest in alternative therapies derived from natural products; accordingly, the present review has compiled the bioactive compounds found in legumes that have demonstrated an anti-inflammatory effect in non-clinical studies.

Tremendous progress has been made in the field of ferroptosis since this regulated cell death process was first named in 2012. Ferroptosis is initiated upon redox imbalance and driven by excessive phospholipid peroxidation. Levels of multiple intracellular nutrients (iron, selenium, vitamin E and coenzyme Q10) are intimately related to the cellular antioxidant system and participate in the regulation of ferroptosis. Dietary intake of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) regulates ferroptosis by directly modifying the fatty acid composition in cell membranes. In addition, amino acids and glucose (energy stress) manipulate the ferroptosis pathway through the nutrient-sensitive kinases mechanistic target of rapamycin complex 1 (mTORC1) and AMP-activated protein kinase (AMPK). Understanding the molecular interaction between nutrient signals and ferroptosis sensors might help in the identification of the roles of ferroptosis in normal physiology and in the development of novel pharmacological targets for the treatment of ferroptosis-related diseases.

Inflammation is a normal part of the immune response and should be self-limiting. Excessive or unresolved inflammation is linked to tissue damage, pathology and ill health. Prostaglandins and leukotrienes produced from the n-6 fatty acid arachidonic acid are involved in inflammation. Fatty acids may also influence inflammatory processes through mechanisms not necessarily involving lipid mediators. The n-3 fatty acids EPA and DHA possess a range of anti-inflammatory actions. Increased content of EPA and DHA in the membranes of cells involved in inflammation has effects on the physical nature of the membranes and on the formation of signalling platforms called lipid rafts. EPA and DHA interfere with arachidonic acid metabolism which yields prostaglandins and leukotrienes involved in inflammation. EPA gives rise to weak (e.g. less inflammatory) analogues and both EPA and DHA are substrates for the synthesis of specialised pro-resolving mediators. Through their effects on early signalling events in membranes and on the profile of lipid mediators produced, EPA and DHA alter both intracellular and intercellular signals. Within cells, this leads to altered patterns of gene expression and of protein production. The net result is decreased production of inflammatory cytokines, chemokines, adhesion molecules, proteases and enzymes. The anti-inflammatory and inflammation-resolving effects of EPA and DHA are relevant to both prevention and treatment of human diseases that have an inflammatory component. This has been widely studied in rheumatoid arthritis where there is good evidence that high doses of EPA + DHA reduce pain and other symptoms.

Asthma is one of the most common and prevalent problems worldwide affecting over 300 million individuals. There is some evidence from observational and intervention studies to suggest a beneficial effect of n-3 PUFA in inflammatory diseases, specifically asthma. Marine-based n-3 PUFA have therefore been proposed as a possible complementary/alternative therapy for asthma. The proposed anti-inflammatory effects of n-3 fatty acids may be linked to a change in cell membrane composition. This altered membrane composition following n-3 fatty acid supplementation (primarily EPA and DHA) can modify lipid mediator generation via the production of eicosanoids with a reduced inflammatory potential/impact. A recently identified group of lipid mediators derived from EPA including E-series resolvins are proposed to be important in the resolution of inflammation. Reduced inflammation attenuates the severity of asthma including symptoms (dyspnoea) and exerts a bronchodilatory effect. There have been no major health side effects reported with the dietary supplementation of n-3 fatty acids or their mediators; consequently supplementing with n-3 fatty acids is an attractive non-pharmacological intervention which may benefit asthma.

Accumulating evidence indicates that, analogous to n-6 PUFA, n-3 PUFA are enzymatically converted into diverse families of bioactive mediators that play numerous roles in physiology. These mediators, which include the resolvins, protectins and maresins, are particularly important in resolving acute inflammation and also appear to play a role in enhancing host defence. Given the protective actions of n-3 PUFA in human subjects and in animal models of disease, active generation of bioactive mediators may in part underlie these protective effects. Several studies have demonstrated that bioactive autacoids generated from n-3 PUFA have direct anti-inflammatory and pro-resolution actions, and the structures of many of these endogenous mediators have been elucidated. The diverse roles of these lipid mediators in health and disease, regulation of their biosynthesis, as well as identification of specific receptors and cellular targets, are emerging. This brief review will highlight the biosynthesis of resolvins, protectins and maresins, and discuss their receptor-mediated biological actions in promoting the resolution of inflammation. Their potential use as a new class of pro-resolution therapeutics, as well as gaps in knowledge and challenges for future research, will also be discussed. Overall, the identification of these novel families of lipid mediators has yielded insight into the protective actions of n-3 PUFA and may lead to the development of an entirely new class of therapeutics aimed at regulating inflammation and host defence.

Uncontrolled inflammation is a contributing factor to many leading causes of human morbidity and mortality including atherosclerosis, cancer and diabetes. Se is an essential nutrient in the mammalian diet that has some anti-inflammatory properties and, at sufficient amounts in the diet, has been shown to be protective in various inflammatory-based disease models. More recently, Se has been shown to alter the expression of eicosanoids that orchestrate the initiation, magnitude and resolution of inflammation. Many of the health benefits of Se are thought to be due to antioxidant and redox-regulating properties of certain selenoproteins. The present review will discuss the existing evidence that supports the concept that optimal Se intake can mitigate dysfunctional inflammatory responses, in part, through the regulation of eicosanoid metabolism. The ability of selenoproteins to alter the biosynthesis of eicosanoids by reducing oxidative stress and/or by modifying redox-regulated signalling pathways also will be discussed. Based on the current literature, however, it is clear that more research is necessary to uncover the specific beneficial mechanisms behind the anti-inflammatory properties of selenoproteins and other Se metabolites, especially as related to eicosanoid biosynthesis. A better understanding of the mechanisms involved in Se-mediated regulation of host inflammatory responses may lead to the development of dietary intervention strategies that take optimal advantage of its biological potency.

In Rhinella arenarum, progesterone is the physiological nuclear maturation inducer that interacts with the oocyte surface and starts a cascade of events that leads to germinal vesicle breakdown (GVBD). Polyunsaturated fatty acids and their metabolites produced through cyclooxygenase (COX) and lipoxygenase (LOX) pathways play an important role in reproductive processes. In amphibians, to date, the role of arachidonic acid (AA) metabolites in progesterone (P4)-induced oocyte maturation has not been clarified. In this work we studied the participation of three enzymes involved in AA metabolism – phospholipase A2 (PLA2), COX and LOX in Rhinella arenarum oocyte maturation. PLA2 activation induced maturation in Rhinella arenarum oocytes in a dose-dependent manner. Oocytes when treated with 0.08 μM melittin showed the highest response (78 ± 6% GVBD). In follicles, PLA2 activation did not significantly induce maturation at the assayed doses (12 ± 3% GVBD). PLA2 inhibition with quinacrine prevented melittin-induced GVBD in a dose-dependent manner, however PLA2 inactivation did not affect P4-induced maturation. This finding suggests that PLA2 is not the only phospholipase involved in P4-induced maturation in this species. P4-induced oocyte maturation was inhibited by the COX inhibitors indomethacin and rofecoxib (65 ± 3% and 63 ± 3% GVBD, respectively), although COX activity was never blocked by their addition. Follicles showed a similar response following the addition of these inhibitors. Participation of LOX metabolites in maturation seems to be correlated with seasonal variation in ovarian response to P4. During the February to June period (low P4 response), LOX inhibition by nordihydroguaiaretic acid or lysine clonixinate increased maturation by up to 70%. In contrast, during the July to January period (high P4 response), LOX inhibition had no effect on hormone-induced maturation.

Introduction. Plum cv. SantaRosa shows climacteric behaviour and grows profitably under sub-temperateconditions in India. After ripening, it has a very limited shelflife (3–4 days) in ambient conditions [(38 ± 2) °C and at (68 ± 4)%RH]. Hence, there is an urgent need to extend its marketabilityusing recent techniques. Materials and methods. Plumswere harvested at the pre-climacteric and climacteric stages ofmaturity and packed with newspaper shreds (control), KMnO4-impregnatedchalks, KMnO4-impregnated newspaper shreds or ethylene-absorbent sachets;then they were transported by road to New Delhi. The biochemicaland physiological analyses were carried out at 3-day intervals onplums stored in supermarket conditions [(20 ± 1) °C and at (90 ± 2)%RH] for 15 days. Results and discussion. Untreatedfruits had less firmness than those which were packed with ethyleneabsorbents. The activities of fruit-softening enzymes such as lipoxygenase(LOX), polygalacturonase (PG) and pectin methylesterase (PME) increasedrapidly in the control treatment in comparison with plums packed withvarious ethylene absorbents, the least being either with ethylene-absorbentsachets or with KMnO4-impregnated newspaper shreds. Plums of pre-climacteric andclimacteric maturity attained respiration and ethylene evolutionpeaks on the 9th day and 6th day, respectively. Conclusions. Theplums of pre-climacteric and climacteric stages of maturity packed withethylene-absorbent sachets showed the best results in supermarketconditions in maintaining the firmness, quality and shelf life ofplum up to the 12th day and 9th day of storage, respectively.

Introduction. Kiwifruit is a typical climacteric fruit, which grows profitably well in sub-temperate climatic conditions. The major problem with kiwifruit is that it does not ripen for about a week at room temperature but after this period there is a sudden rise in the respiration rate and fruits remain in edible condition for only a few days, giving it a very short shelf life in ambient conditions. Materials and methods. Kiwifruits were treated with different concentrations of spermine [(0.5, 1.0 and 1.5) mM] and spermidine [(1.0, 1.5 and 2.0) mM] by the immersion method; biochemical and physiological analyses were carried out, then fruit were stored in ambient conditions for 15 days. Results and discussion. Polyamine-treated fruits did not show any amount of ethylene evolution up to the 6th day of storage as compared with those of control, in which it started after the 3rd day of storage. The respiration rate was also the lowest in treated fruit. Similarly, polygalacturonase and lipoxygenase activities rose rapidly in control fruits in comparison with polyamine-treated fruits. Conclusion. The doses of spermine at 1.5 mM and spermidine at 2.0 mM showed the best results in extending the shelf life of kiwifruits when stored in ambient conditions [(22 ± 4) ◦C, RH: (65 ± 5)%].

Investigations of physiological functions of seed lipoxygenase during germination and early seedling growth are complicated by the presence of multiple isoforms with different product specificity. The combination of isoelectric focusing, lipoxygenase in-gel activity staining and mass spectrometry showed that only two seed lipoxygenases, LOX-2 and LOX-3, were active at neutral pH in protein extracts from dry and germinating pea seeds (Pisum sativum L.), with LOX-3 more abundant than LOX-2. Each active seed LOX appeared at multiple pIs, probably resulting from post-translational modifications. The abundance of pea seed lipoxygenases was lower in embryonic shoots than in other parts of the axis. After radicle emergence, seed LOXs were degraded, as revealed by Western blotting using antibodies specific to pea seed LOXs. Two new vegetative isoforms, LOX-N3 and LOX-g, appeared in the shoot and gradually replaced the pea seed lipoxygenases as the principal contributors to LOX enzyme activity during early seedling growth. Activities of LOX-N3 and LOX-g were abundant in shoot tips, but not root tips, in pea seedlings. Thus, during germination, there is a shift of LOX activity from radicles to shoots that accompanies the transition from seed LOXs to vegetative LOXs. These results confirmed that identification of pea LOXs based solely on pI may be misleading; however, mass spectrometry enabled more accurate identification of these highly homologous proteins to be made.

The aim of this study was to investigate whether there was a relationship between growth of sunflower seedlings at 15°C in the dark and activities of enzymes involved in scavenging of reactive oxygen species (ROS), especially superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR), or in production of free radicals, namely lipoxygenase (LOX). Untreated control seeds were compared with seeds exposed to accelerated ageing (5 d at 45°C and 100% relative humidity), osmopriming (7 d at 15°C with a polyethylene glycol (PEG) solution at –2 MPa) and accelerated ageing followed by priming. Accelerated ageing decreased seed germinability and slowed down hypocotyl growth, whereas priming resulted in an increase in germination rate and enhanced seedling development. Osmopriming of aged seeds almost completely restored the initial rate of germination and seedling growth. The activity of all the enzymes studied increased during seed germination and seedling development, except that of SOD. Seed imbibition or radicle protrusion were related mainly with an increase in CAT activity and, to a lesser extent, in GR activity. Increase of LOX activity was clearly associated with the onset of hypocotyl elongation. However, in all cases, malondialdehyde measurements did not reveal intense lipid peroxidation. Priming induced a marked stimulation of CAT and GR during seed imbibition or very early during seedling development, as compared to the control seedlings and particularly to the seedlings generated by aged seeds. Hydrogen peroxide (H2O2) contents of seeds and seedlings were closely correlated to the activities of CAT and GR and to the kinetics of seedling development. The results obtained establish a clear relationship between sunflower seed vigour and ROS scavenging.

A search for the occurrence of the rare π-helix was performed with Iditis from the Oxford Molecular Group upon the Protein Data Bank. In 8 of the 10 confirmed crystal structures that harbor the π-helix, its unique conformation has been linked directly to the formation or stabilization of a specific binding site within the protein. In the discussion to follow, the role for each of these eight π-helices will be addressed in regard to protein function. It is clear upon closer examination that the conformation of the π-helix has evolved to provide unique structural features within a variety of proteins.